Merge ~brad-marshall/charm-prometheus-openstack-exporter/+git/promtheus-openstack-exporter-charm:add-nem-interface-fix-metadata into ~prometheus-charmers/charm-prometheus-openstack-exporter/+git/prometheus-openstack-exporter-charm:master

[Brad Marshall]

Added nrpe-external-master interface and a http check, fix some metadata details

[James Hebden (ec0)]

LGTM

review: Approve

diff --git a/config.yaml b/config.yaml
index 0ccae6e..faf8cea 100644
--- a/config.yaml
+++ b/config.yaml
@@ -50,3 +50,17 @@ options:
     description: |
         If install_method is set to "snap" this option controlls channel name.    
         Supported values are: "stable", "candidate", "beta" and "edge"
+  nagios_context:
+    default: "juju"
+    type: string
+    description: |
+      A string that will be prepended to instance name to set the host name
+      in nagios. So for instance the hostname would be something like:
+          juju-myservice-0
+      If you're running multiple environments with the same services in them
+      this allows you to differentiate between them.
+  nagios_servicegroups:
+    default: "juju"
+    type: string
+    description: |
+      Comma separated list of nagios servicegroups for the graphite check
diff --git a/layer.yaml b/layer.yaml
index fef8dd8..a51fd28 100644
--- a/layer.yaml
+++ b/layer.yaml
@@ -2,6 +2,7 @@ includes:
     - 'layer:basic'
     - 'layer:snap'
     - 'interface:http'
+    - 'interface:nrpe-external-master'
 # Included in the charm itself, see hooks/*relations*
 #    - 'interface:keystone-credentials'
 #    - 'interface:swift'
diff --git a/metadata.yaml b/metadata.yaml
index e612d05..a296e6a 100644
--- a/metadata.yaml
+++ b/metadata.yaml
@@ -1,10 +1,13 @@
 name: prometheus-openstack-exporter
-maintainer: [e-mail]
-summary: Short summary of charm
+maintainer: Prometheus Charmers <[e-mail]>
+summary: Openstack exporter for Prometheus
 description: |
-  Longline summary of charm 
+  This is an exporter that exposes information gathered from Openstack
+  for use by the Prometheus monitoring system.
 tags:
   - openstack
+  - monitoring
+  - prometheus
 requires:
   identity-credentials:
     interface: keystone-credentials
@@ -12,7 +15,10 @@ requires:
     interface: swift
 provides:
   prometheus-openstack-exporter-service:
-      interface: http
+    interface: http
+  nrpe-external-master:
+    interface: nrpe-external-master
+    scope: container
 series:
   - xenial
   - trusty
diff --git a/reactive/openstack_exporter.py b/reactive/openstack_exporter.py
index 2182d07..f5aa6c8 100644
--- a/reactive/openstack_exporter.py
+++ b/reactive/openstack_exporter.py
@@ -32,6 +32,7 @@ from charmhelpers.core import (
 )
 from charmhelpers.core.templating import render
 from charms.layer import snap
+from charmhelpers.contrib.charmsupport import nrpe
 
 SNAP_NAME = 'prometheus-openstack-exporter'
 SVC_NAME = ('snap.prometheus-openstack-exporter.'
@@ -195,3 +196,17 @@ def do_restart():
 def configure_exporter_service(exporter_service):
     config = hookenv.config()
     exporter_service.configure(config.get('port'))
+
+
+@when('nrpe-external-master.available')
+def update_nrpe_config(svc):
+    hostname = nrpe.get_nagios_hostname()
+    nrpe_setup = nrpe.NRPE(hostname=hostname)
+    config = hookenv.config()
+    port = config.get('port')
+    nrpe_setup.add_check('prometheus_openstack_exporter_http',
+                         'Prometheus Openstack Exporter HTTP check',
+                         'check_http -I 127.0.0.1 -p {} -u /metrics'.format(port)
+                         )
+    nrpe_setup.write()
+